CLARKSVILLE, Tenn. — At least three women have been charged with promoting prostitution this week after undercover officers responded to online ads which offered sex for money.

Two women were arrested in separate cases Tuesday. Another was arrested Dec. 10.

According to arrest warrants, Clarksville Police Department's Special Operations Unit were conducting "a prostitution operation targeting those offering sexual encounters in exchange for money through an advertisement on the internet site Backpage.com."

On Tuesday, an undercover officer called Kanietha Alexander, 28, of Hopkinsville and arranged to meet at a Baltimore Drive apartment in Clarksville, according to an arrest warrant.

The warrant says she offered sexual services starting at $120.

When she arrived at the apartment she was arrested and charged with promoting prostitution, prostitution, unlawful drug paraphernalia and simple drug possession.

Alexander was booked into the Montgomery County Jail on $31,500 bond.

Also on Tuesday, Special Operations agents contacted Amy Ferrell, 24, of Shelbyville and arranged a sexual encounter for $160, according to her arrest warrant.

She told an undercover officer to meet her at a Holiday Drive hotel room and opened the door when agents arrived, the warrant says.